* feat: add TOTP two-factor authentication for dashboard login
* fix: ensure TOTP verification uses UTC for accurate time comparison
* fix: update recovery code validation logic for disabling TOTP
* test: add unit tests for TOTP functionality and recovery code validation
* chore: format
* feat: add trust_proxy_headers switch for auth rate-limit IP source
* feat: make dashboard auth rate-limit configurable via system settings
Add auth_rate_limit config block to dashboard settings with enable
(default: true), average_interval (default: 1.0s), and max_burst
(default: 3) options. The dashboard auth middleware now reads from
config instead of using hardcoded values. The average_interval and
max_burst fields are conditionally shown only when rate limiting is
enabled.
* fix: normalize dashboard client IP from trusted proxy headers
* refactor: encapsulate rate limiter state into registry, add TTL
* feat: show dynamic page title during two-factor verification
* fix: require two-factor verification for protected config saves
* chore: format
* refactor: reorganize TOTP verification UI components for better layout
* refactor: clean up recovery stage UI by removing unused styles and improving label handling
* docs: add TOTP two-factor authentication documentation for WebUI
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Co-authored-by: Soulter <905617992@qq.com>